比例減衰を持つ二自由度動吸振器による二自由度系の制振

抄録

The vibration suppression characteristics of two DOF dynamic absorber with proportional damping coefficients for two DOF system are investigated. We found that there are no fixed points in the frequency response function, but there are four concentration points for small proportional coefficients for the damping. Two concentration points are near the first natural frequency of original system, and another two concentration points are near the second natural frequency. Then we treat the concentration points as the fixed points, and the fixed points theory by Den Hartog is applied. The dynamic absorber with mass proportional damping is more efficient than stiffness proportional damping, but the difference is a little. Then the dynamic absorber with stiffness proportional damping is practical because the mass proportional damping means the sky hook damper and is difficult to install.